Households spend thousands of dollars a year on buying food that goes uneaten. There’s been considerable research looking into why people waste food. The common reasons are that people buy too much food, don’t store it correctly, serve too much on their plates and don’t eat their leftovers

But how can you help households change these habits?

I sat down with Stine Knudsen, a behavioural designer working for the City of Copenhagen to find out. Stine shared with me the unique approach that Copenhagen is taking to help households reduce their food waste. Out of our discussions emerged some key lessons and principles for designing effective behaviour change campaigns.

Lesson #1 Do your homework

The City of Copenhagen did research that found half of their population decide what to eat for dinner when standing in the shop on the same day. This habit can lead to overbuying food especially if people are tired and hungry when shopping and/or haven’t had the chance to check their fridge to see what ingredients they already have at home.

Copenhagen is currently testing a behaviour change initiative where they’re asking households to decide what to eat for dinner just one day before. This is expected to help them to reduce their food waste. The results from the pilot will be available in the next few months.

Interestingly, Stine says the same campaign would not work for people living in rural areas of Denmark because they have different shopping habits. Unlike Copenhagen, rural areas don’t have shops on (nearly) every street corner and there are different reasons why people living there waste food. It also wouldn’t work for singles who typically eat takeout rather than shop for groceries.

So the takehome message is to make sure to do your homework before rolling out a behaviour change campaign. Don’t assume that because a campaign works in one city or for one demographic that it will transfer to another. Consider the unique shopping habits of different groups of people in your city.

Lessons #2-5

2. Applying the 80:20 rule. Don’t overwhelm people with too many messages on how to reduce food waste. Focus on changing a few larger habits that will have the biggest impact.

3. Teach people to trust their senses. A lot of people throw out edible food because it’s passed the ‘best before’ date. Copenhagen has developed simple rule of thumb to help people evaluate whether or not food is safe to eat before deciding to throw it away.

4. Try and get your message on food waste as close to the fridge as possible. Instead of putting ads on bus shelters, work with supermarkets to influence messaging on food packaging or deliver a food waste kit directly to households.

5. Test, test and test again. It’s always worth trialing and refining approaches to see what works before investing big money in a campaign. For example, Copenhagen trialed teaching residents to reorder the contents of their fridges based on cooling zones to reduce food waste. They found people resisted this because people liked packing their fridges the way their families did when growing up. Instead, Copenhagen refined their initiative to ask people to create one shelf in their fridge dedicated for food that needs to be eaten soon to prevent it from being forgotten at the back of the fridge. They provided residents with an “Eat Soon” sticker for the shelf and encouraged them to place their leftovers, open packets of meat and dairy there. This has proved a very popular approach for helping families to reduce food.

For further insights and our full interview, listen to the recording below.

About Stine Knudsen

Mrs. Stine R.K. Knudsen is currently a project manager in the Technical and Environmental Administration in the Municipality of Copenhagen. As a behavioral designer, she currently works with reduction of avoidable food waste from households and how to increase recycling through social norms.

We have few shots in the barrel as a municipality. Getting people to change habits and listen to new advice is very difficult. That’s why we’re looking to find the 3 things that will have the maximum effect… That’s why we’re focusing on the larger habits rather than individual tips on reducing food waste…

We’re trying to give them general advice that you can trust your senses… It wouldn’t say “best before” unless you could tell if it was okay to eat.